This invention relates generally to power plant construction and, specifically, to a unique and reusable pipe flange cover that protects pipe flanges from damage and prevents debris from entering the pipe opening surrounded by the flange, primarily during storage and shipment and prior to installation in the plant.
Construction of a power plant involves the manufacture and assembly of many and various styles and sizes of flanged pipe assemblies. A major requirement in the manufacture and assembly of these flanged pipe assemblies is that they are clean and free of foreign debris between the time they are manufactured and the time they are installed. Existing flange cover designs fall into two categories:
a. Metal flange covers with rubber gaskets held in place by the use of nuts and bolts. These covers protect the flange face, seal the pipe opening, and make use of the bolt holes in the flange to secure the cover in place. This configuration, however, requires tools to install and involves a cumbersome procedure. Due to the weight of the flange and the requirement to use nuts and bolts to secure the cover to the flange, it is often either not properly installed, or not properly re-installed when taken off for any reason. An example of this type cover is shown in FIGS. 1 and 2 and described further herein.
b. Plastic covers of various configurations. The plastic covers do an adequate job of protecting the flange face but do not adequately seal the pipe opening. The plastic tends to warp when exposed to sunlight or extreme temperature variations. The majority of this type of flange cover do not have positive retention methods, and therefore they tend to come off during use. An example of a plastic cover is shown in FIGS. 3 and 4 and also described further herein.
This invention relates to a molded plastic cover that completely covers the pipe opening and pipe flange face and, is secured to the flange by pushing resilient or spring-type lugs that protrude from the rear of the cover into the bolt holes in the flange. The flange cover includes a bellows-type arrangement that accommodates both flat face flanges and raised face flanges. The bellows also compensates for variations in flange thickness and acts to seal debris from the interior of the pipe.
No tooling is required for installation or removal of the cover, but it is held securely in place by the spring lugs, and the cover is also designed to be reusable.
Thus, in its broader aspects, the invention relates to a pipe flange cover for temporarily covering a pipe opening and a pipe flange at an end of a pipe, the cover having a front face and a rear face, the rear face having a center portion and a peripheral portion, the peripheral portion formed with a plurality of axially projecting spring lugs; the center portion adapted to engage a front side of the pipe flange and to seal the pipe opening, the spring lugs adapted for insertion into bolt holes on the pipe flange; and wherein the center portion is axially offset from the peripheral portion.
In another aspect, the invention relates to a pipe flange cover for temporarily covering a pipe opening and a pipe flange at an end of a pipe, the cover having a front face and a rear face, the rear face having a center portion and a peripheral portion, the peripheral portion formed with a plurality of axially projecting spring lugs; the center portion adapted to engage a front side of the pipe flange and to seal the pipe opening, the spring lugs adapted for insertion into bolt holes on the pipe flange; and wherein the center portion is axially offset from the peripheral portion but connected thereto by an integral bellows.